This invention relates to apparatus for the emergency plugging of a hole in the hull of a boat.
A number of emergency plugging devices for that purpose in the general nature of an umbrella have been proposed hitherto. For example, the device of British patent 1,450,861 to B. Simpson, in which the device is thrust outwardly through the hole in the boat, then "opened", that is to say unfurled or extended in the manner of an umbrella, and allowed to come back against the outer surface of the hull to at least diminish the inflow of water. It has been found that such known devices are difficult to use in practice because it is quite hard to open the device against the pressure of the inrushing water.
In prior attempts to achieve rapid opening it has been proposed to utilise spring loaded mechanisms, for example the device of British patent application 2,217,591 of G. W. Kassbaum, but such mechanisms rapidly corrode and freeze up in a marine environment and are likely to be inoperative when called upon in an emergency after a long period of non-use.